Automatic vehicle-brake



m T I W E H H L (No Model.)

AUTOMATIC-VEHICLE BRAKE.

Patented Apr. 14, 1896,

AN DREW B GRAHAMplO'TO-UTNQWAHlNGION, D C

(No Model.) 2 Sheets-Sheet 2.

r L. H. HEWITT. AUTOMATIC VEHICLE BRAKE.

Patented Apr. 14; 1896.

UNITED STATES PATENT OFFICE...

LEWIS I-l. HEXVITT, OF LOCKE, NEWV YORK.

AUTOMATIC VEHICLE-BRAKE.

SPECIFICATION forming part of Letters Patent No. 558,17 5, dated April 14:, 1896. Application filed October 11, 1895. Serial No. 565,367. (No model.)

To all whom it may concern.-

Be it known that 1, Lewis H. HEWITT, a citizen of the United States, residing at Locke, in the county of Cayuga and State of New York, have invented certain new and useful Improvements in Automatic Vehicle Brakes; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to improvements in automatic brakes for vehicles; and the object that I have in view is to provide a simple and compact arrangement of parts which are so combined that when the animal pulls back, as when descending a hill or declivity, the brake -shoes will be automatically applied against the wheels to retard the descent of the vehicle and in which the brake-shoes are normally thrown ofi or out of contact with the wheels when the animal is pulling the vehicle.

A further object of the invention is to provide means which may be adjusted to prevent under some circumstances the application of the brake-shoes to the wheels.

With these ends in view my invention consists in the combination, with the thills, the connecting cross-bar of said thills, and a whiffietree, of two angular levers disposed below the connecting thill-bar and having their innor ends pivoted on the same bolt Which connects the whiflietree to the connecting-bar, brake-shoes carried by the outer ends of the angular levers, endwise-movable rods below the thills having their rear ends connected to the angular levers and provided at their front ends with loops which embrace the thills and are adapted to receive straps connected to the breeching of the harness, and a leaf-spring supported by a clasp which is connected with thewhiffletree pivotal bolt, the free ends of said spring being arranged to bear or press against the angular levers, so as to normally force said levers forward and thus throw the brake shoes away from contact with the wheels.

Under some circumstances it is desirable to prevent the application of the brake-shoes to the wheels of the vehicle when the horse pulls backas, for instance, when the vehicle is to be backed up to and against a curbing of a pavement for the purpose of conveniently removing the load from the vehicle or putting the load therein. It is therefore necessary to provide means which will render the application of the brake-shoes to the wheels of no eifect in so far as regards retarding the back- .w-ard movement of the wagon under the circumstances just mentioned. This result may be accomplished in a variety of ways. In case the brake is used on a light carriage,

wagon, or other vehicle I may employ brakewhen the vehicle is being backed against a curbing and the wheels are rotated in the reverse direction the contact of the slotted brake-shoes with the wheels has a tendency to force the brake shoes upwardly and away from the wheels, thus preventing the brakeshoes from materially retarding the backing of the vehicle.

When the brake is used on heavy wagons or other vehicles for haulage purposes, the slotted brake-shoes may not be sufficient to retard the vehicles. In such a case I fasten the brake-shoes rigidly t0 the brake-levers, and provide means for'positively arresting the backward movement of the angular brakelevers. The brakelever-arresting device may be embodied in a variety of ways, and in this specification I will refer .to two embodiments of this part of the invention. In one construction of the means for arresting the backward movement of the brake-levers a horizontal rock-shaft is j ournaled below the thills in rear of the brake-levers, and on this rock-shaft are provided arms, which, when the rock-shaft is turned to adjust said arms in the path of the brake-levers or in contact therewith serve as stops to prevent or arrest the backward movement of the brake-levers when the rods push back on said brake-levers,

said rock-shaft being controlled by means of a lever arranged within convenient reach of the driver seated in the vehicle.

Another embodiment of the arresting device for the brake-levers consists in providin g stops arranged to lie thrown into the path of the brake-levers, and a sliding rod pivoted to said stops and connected with a suitable operating shaft or lever, whereby movement of the rod in one direction operates to throw the pivoted stops into the path or in contact with the brake-levers, but when the rod is moved in the opposite direction the stops are reversed or turned to a position where they do not interfere with the backward movement of the brake-levers.

To enable others to understand my invention, I have illustrated the same in the accompanying drawings, forming a part of this specification, and in which Figure 1 is a plan View of my brake applied to the thills, showing by dotted lines so much of a vehicle as is necessary for an understanding of the same. Fig. 2 is a side elevation illustrating the preferred form of the brakeshoe. Fig. 3 isa vertical cross-sectional view on the plane indicated by the dotted line 00 as of Fig. 1. Fig. 4 is a detail view of one of the angular levers, showing the brake-block detached from said lever. Figs. 5 and G are detail views of the means for preventing the backward movement of the brake-levers when it is desired to back the vehicle against a pavement-curbing.

Like letters of reference denote correspond ing parts in all the figures of the drawings, referring to which- A designates the thills, B the cross-bar which connects the thills rigidly together, and

C is the whiffletree, all of which parts are similar to the ordinary devices now in use.

D E designate the two angular levers, which are arranged below the thill-bar B. Each angular lever is preferably in one piece, and it is shaped to provide the forwardly-extending arm 01 and the outwardly-extending arm 6. The straight arm of the lever has an eye or opening d, and these eye-formed inner ends of the levers D E are pivotally connected to the lower end of the pivotal bolt F, which passes through the whiffietree O and the crossbar B, whereby the bolt F serves to pivotally support the two angular levers and the whiffletree on the cross-bar B. The forwardlyextending arms d cl of the two angular levers are arranged below the rearparts of the thills and extend forward a sufficient distance to carry the arms e e forward of the wheels, (see Fig. 1,) while the outwardly-extending arms 8 e of the levers extend in opposite direct-ions beyond the sides of the thills A A a sufficient distance to enable the brake blocks or shoes G G to properly bear or ride against the wheels. These brake-shoes G G may be rigidly attached to the outer ends of the angular levers in a suitable manner.

At the angular portion of the leversi. e.

where the arms d e are joined togetheran eye or opening e is formed in each lever, and to these eyes or openings of the two levers are pivotally connected the rear ends of the endwise-movable rods H H. These endwise-movable rods H H extend from the levers D E along the under side of the thills A A for a suitable distance, and near their forward ends these rods H are provided with the loops 71. These loops h are loosely fitted on the thills A, so as to be free to slide thereon with the rods 11, and said loops serve to support the front ends of the rods on the thills. The loops 7b are constructed to enable straps to be attached thereto, and these straps are adapted to be fastened to the breeching of the harness in a manner which will'be readily understood.

The pivotal bolt F receives the ends of a loop f, through which is passed the spring J. This spring is of the leaf-spring variety, and its central part is held in the loop f by means of the pin f. The ends of the spring are free, and they bear or press against the rear sides of the angular levers in order to push or throw the levers forward and thus hold the brakeshoes from contact with the wheels.

The operation of my improved brake as thus far described may be described briefly as follows: When the horse-is pulling the vehicle, the brake-shoes are free from contact with the wheels, because the brake-leversD E are pressed forward by the leaf-spring J. On descending a hill or declivity the horse is reined up or pulled back to cause the breeching to pull back on the rods H H, and these rods actuate the levers D E against the tension of the spring J to force the brake-shoes against the wheels of the vehicle, thereby retarding the movement of the vehicle. In backing the wagon against a curb or in turning the vehicle around it is not desirable to apply the brake, but as the rods H are pulled back to press the levers D E backward the brakeshoes willbe applied against the wheels unless some construction is provided which renders the pressure of the brake-shoes against the wheels of no avail so far as respects retarding the vehicle. This result may be secured by a novel construction of the brake-shoe, as represented in Figs. 2 and 4, or by the employment of devices designed for manual adjustment which will prevent the backward movement of the brake-levers.

The brake-block G (shown by Figs. 2'and 4) has a vertically-inclined or diagonal slot or cut through the same, and through this slot n passes a threaded tenon n on the outer extremity of the arm e of the brake-lever. The brake-block is adapted to bear against a shoulder n on the brake-lever, and it is held loosely in place on the lever by a nut 11', which is screwed on the threaded tenon n. Normally the brake-block drops down by gravity, so that the tenon n. rests in the upper end of the diagonal slot, and this block is held free from the wheel by the brake-lever being pressed forward by the spring. When the wagon is descending a hill or declivity, the wheels turn in the direction indicated by the arrow in Fig. 2, and as the rods H push the levers D E backward the shoes G bear against the wheels. As the wheels rotate in the direction indicated by the arrow, the contact between the wheels and the brake-blocks has a tendency to draw the slotted blocks G downward, so that the blocks can be held firmly pressed against the wheels to retard the descent of the vehicle. When the vehicle is backed or turned and the brake-blocks are pressed by the levers against the wheels, the wheels rotate in the reverse direction to that indicated by the arrow in Fig. 2. Hence the contact of the brake-blocks with the wheels has a tendency to cause the slotted loose blocks to move upward, and thus the blocks do not materially retard the wheels under such circumstances.

While the employment of the slotted brakeblocks serves advantageously in case of their use on light vehicles, for brakes to be used on large heavy vehicles I prefer to employ a mechanically-adjustable stop mechanism to positively prevent the backward movement of the brake-levers. Two embodiments of such stop mechanism are illustrated by Figs. 1, 2, and 6 and by Fig. 5, respectively. In the construction shown by Figs. 1, 2, and 6 a rock-shaft K is provided with stop-arms 10 7c and an operating-lever K. This rock-shaft is journaled in suitable bearings in this thill A, in rear of the connecting-bar B, and when the lever is thrown in one direction the rockshaft is turned to move its arms in is out of the way of the brake-levers to permit them to move backward and apply the brake-shoes against the wheels; but when the lever is moved in the opposite direction the rock-shaft is turned to move the stop-arms in the path of or directly against the brake-levers to prevent them from being pushed back by the rods H and applying the brake-shoes to the wheels.

In the construction shown by Fig. 5 two stops L L are pivoted at Z to suitable brackets fastened to the thills, and these pivoted stops are connected by a slidablebar or rod L, which may be moved in eitherdirection bya lever or stem, the ends of the rod or bar L being pivoted to the ends of said stops L L. The stops are arranged quite close to the brake-levers, back of the same, and when the stops occupy the positions shown by Fig. 5 their free ends are adapted to rest against or lie in the path of the brake-levers to prevent them from moving backward when the rods H push against the same; but when the rod or bar L is moved inone direction bya lever or stem operated by the driver these stops are turned to the positions indicated by the dotted lines, and thus the stops are withdrawn from the levers D E suiiiciently for said levers to move back far enough to apply the brake shoes or blocks to the wheels. however, limit myself to the precise means herein shown and described for arresting the backward movement of the brake-levers, nor to the specific construction and arrangement of parts herein shown and described as the preferred embodiment of the invention, but reserve the right to make such modifications and alterations as fairly fall within the scope of my invention.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is-- 1. The combination with the thills and the cross-bar, of the angular levers arranged beneath the thills and the connecting-bar, a pivotal bolt which connects the angular levers to the connecting-bar, brake-shoes carried by the outer ends of the angular levers, the endwise-movable rods pivoted to the bent portions of the angular levers, and a single spring pressing against the two levers to normally force the same forward and hold the brakeshoes free from contact with the wheels, substantially as and for the purposes described.

2. The combination with the thills, the cross-bar, and a whiffletree, of the levers arranged beneath the cross-bar and having the arms 01, e, the pivotal bolt F passing through the inner ends of the levers, the cross-bar, and

the whiffletree, the leaf-spring supported in a clip attached to the bolt and having its free ends bearing against the two levers, the rods pivoted to the levers and provided with the strap-receiving loops which are loosely fitted on the thills, and the brake-shoes carried by the arms 6, e of the levers, substantially as and for the purposes described.

3. The combination with the thills,of brakelevers carrying suitable brake-shoes, slidable rods connected to said brake-levers, pivoted stops arranged to be thrown into and out of the path of said brake-levers, a slidable bar pivoted to said stops and adapted to shift the same simultaneously, and a shifting-rod at tached to the slidable bar, substantially as and for the purposes described.

In testimony whereof I affix my signature in presence of two witnesses.

LEWIS I-LIIEWITT.

lVitnesses:

JOHN W. TAYLOR, A. O. McINrosH.

I do not, 

